Korehira Watanabe is one of the last remaining Japanese swordsmiths. He has spent 40 years honing his craft in an attempt to recreate Koto, a type of sword that dates back to the Heian and Kamakura periods (794-1333 AD). No documents remain to provide context for Watanabe’s quest, but he believes he has come close to creating a replica of this mythical samurai sword.